Streusel Topping
1/2 cup flour
1/2 cup light brown sugar
2 tbsp sugar
1/4 tsp salt
1/4 tsp cinnamon
2 ounces unsalted butter
The Batter
1 1/2 cups flour
1 1/2 tsp baking powder
5 ounces unsalted butter
2/3 cup sugar / 4 2/3 ounces
1/2 tsp salt
zest of 1 lemon
2 tsp vanilla
2 large eggs
4 cups blueberries
Pan: 9 inch springform
Temperature: 350 degrees
Baking time: 55 minutes
* Check after about 50 minutes